Managing the data traffic in a ring network, such as an Ethernet Ring, involves two general procedures: determining the applicable bandwidth parameters at each point in the ring; and moderating the actual (real-time) data traffic at each point according to the applicable bandwidth parameters.
Bandwidth parameters take into account factors including, but not limited to: Quality of Service (QoS); Class of Service (CoS); Class Type (CT); ringlet (also denoted as “ring side”, being one of: “inner” and “outer”); and failure protection scenario. Moreover, rates are categorized in terms of Committed Information Rate (CIR) and Excess Information Rate (EIR), as well as combinations thereof in cases of shared resources.
Moderating the real-time traffic is typically done via hardware modules which detect real-time traffic rates, and which buffer and schedule transmission of data packets according to various prior-art strategies and algorithms. A typical goal of traffic management is to minimize network latency, especially for high-priority classes of service, by versatile utilization of bandwidth resources. At the same time, however, it is also desired to avoid traffic congestion, because this can cause failures in sustaining QoS for certain classes. It is therefore highly desirable to know the details of the available bandwidth distribution in order to moderate real-time traffic efficiently while minimizing the probability of congestion.
The available bandwidth distribution (as a function of the factors listed above) typically varies, however, especially in cases of node and/or segment failure. Failure of a single node and/or segment typically has an effect on the available bandwidth throughout the ring, and the effect is typically different from one node to another.
Unfortunately, however, when configuring or reconfiguring a network ring, the network elements currently have limited information about the available bandwidth parameters, and therefore cannot configure traffic management in the best way possible.
There is thus a need for, and it would be highly advantageous to have, an improved way of dependably determining the available bandwidth parameters of a ring network and thereby providing efficient traffic management functionality to the network elements thereof. This goal is met by the present invention.